In an example of this kind of power control system, a device requests a breaker device for use permission in use, the breaker device determines whether to permit the use, and the device operates within electric power permitted by the breaker device (for example, see Patent Document 1).
FIG. 14 is a configuration diagram of a related-art power control system disclosed in Patent Document 1, and FIG. 15 is a flow chart showing the processing operation of a device.
In FIG. 14, a power line network includes a breaker device 101, a power line 102, outlets 103A to 103D, devices 104 to 106, and a power supply line 107.
In the above configuration, in the operation shown in FIG. 15, it is assumed that control units of the devices 104 to 106 have detected a trigger caused by power consumption of a certain value or more (S101). For example, this is a phenomenon, such as turning-on of a power supply or an increase in a set temperature in the case of an iron, turning-on of a power supply or a change in a set temperature in the case of an air conditioner, or turning-on of a power supply or the start of discharge of an internal microwave in the case of a microwave oven. The control unit detects the value of power consumption (referred to as P) necessary for this (S102).
Then, a power use request message is generated. The power use request message includes a control code indicating that this is a power use request message, and the value of P as the amount of requested power (S103).
Then, at the device side, the devices 104 to 106 which have received a use permission message containing the amount of allowed usable power A determine whether it is reasonable to operate themselves with reference to the values of the amount of allowed usable power indicated in the use permission message (S104 to S107). If this value of electric power is a requested value, the consumption of electric power is started with this power consumption (P) without any problem (S108). Even if the allowed power consumption (A) is smaller than the requested value (P), the consumption of electric power is started with the power consumption (A) if it is determined that power consumption of this value is reasonable (S109). If it is determined that the power consumption of this value is not reasonable, performing the consumption of electric power is stopped (S110).
In this way, in the power supply network, it is possible to control the amount of supplied power of a fixed amount or less and to efficiently distribute electric power.    Patent Document 1: JP-A-10-94199